Influence of thermal aging on oxidation performance of soot
1. Key Laboratory of Fluid and Power Machinery, Ministry of Education， Xihua University, Chengdu, Sichuan 610039, China; 2. School of Automotive and Transportation Engineering, Xihua University, Chengdu, Sichuan 610039, China
Abstract： Diesel exhaust particle may be suffered thermal aging by high temperature exhaust gas, because it can not be regenerated immediately after being filtered by diesel particle filter (DPF). Based on thermal gravimetric analyzer (TGA), the effects of thermal aging on oxidation characteristic of soot under the condition of different temperatures, time and oxygen concentrations were investigated. The microstructures of corresponding aging particles were determined by the high resolution transmission electron microscopy (HRTEM) and compared with thermal test results. The results show that the activation energy of soot is gradually increased with the increasing of aging temperature. With the increasing of aging time, the activation energy is increased approximately linear first with latter unchanging. Compared with the thermal aging without oxygen, the activation energy of soot treated by thermal aging with oxygen is relatively higher, and the oxygen concentration has slight influence on the activation energy. When temperature, duration time and oxygen concentration of thermal aging are increased, the diameter and the core area of the basic carbon are decreased，and the outer structure is changed more compacter to form a steadier shell.
2018, Vol. 39 
